1. Field of the Invention
This invention relates generally to financial transaction cards, including credit cards, debit cards, ATM (Automated Teller Machine) cards, and the like. More particularly, the invention relates to financial transaction cards that are transparent or translucent to human viewing yet can be detected by sensing devices in automated card processing equipment, such as embossing/encoding machines employed during card manufacturing, and card readers, such as those found in ATMs, automated fuel dispensers, and other point-of-sale card processing equipment.
2. Description of the Prior Art
For some time, financial institutions have been interested in offering financial transaction cards having areas that are transparent or translucent to human viewing. Prior art efforts to achieve such design effects have produced the following examples:                Cards incorporating transparent or translucent films.        Cards incorporating transparent or translucent magnifying lenses.        Cards incorporating transparent or translucent holograms.        Cards incorporating transparent or translucent lenticular patterns.        Cards incorporating other transparent or translucent optical effects.        Cards that are partially transparent or translucent, but also have a high level of opacity provided by the presence of coating(s) containing fillers or pigmentation.        
The perceived advantage of a transparent or translucent financial transaction card is that the card will be relatively unique in the marketplace and impart status to the card user as compared to other users who have only opaque cards. A bank or other entity offering a transparent or translucent card can potentially attract users who will preferentially select such a card over competitive opaque cards, and thereby provide income to the institution as a result of card usage.
A significant problem with transparent or translucent cards is that the cards also need to function properly when processed during manufacture in card embossing/encoding equipment, and when deployed by users in card readers, such as those found in ATMs, automated fuel dispensers, and other point-of-sale card processing equipment. These machines utilize light transmission-based card sensing devices that are not able to detect the presence of transparent or translucent cards. This is due to the fact that the sensing devices, which typically comprise opposing source/detector pairs, are not able to see such cards as opaque (light blocking). The light emitted from the sensing device light sources located on one side of a transparent or translucent card passes through the card rather than being blocked from reaching the detectors located on the other side of the card.
Accordingly, there is a need for a transparent or translucent financial transaction card that overcomes the foregoing problem. What is required is a financial transaction card that is transparent or translucent to human viewing in one or more areas of the card, yet which is detectable by automated card processing equipment, of any type.